Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 9/30/2012
Publication Date: 11/21/2012
Citation: Berrang, M.E. 2012. Campylobacter and Salmonella in broiler processing – transport through chill. XIII International Seminar on Poultry Production and Pathology. November 21-23, 2012. Vina del Mar, Chile. P.1-4.
Interpretive Summary: Salmonella and Campylobacter are human pathogens associated with poultry and poultry products. Both of these organisms are thought to originate on the farm and generally enter the processing plant with the live broilers. Once in the plant, broilers may become cross contaminated or contamination may be spread from internal organs to edible meat surfaces. Transport of broilers in contaminated coops has been shown to be a source of Campylobacter to previously uncontaminated broilers. Coop contamination can be difficult to eradicate; however, we have shown that drying the surfaces is an effective means to eliminate Campylobacter from broiler transport coops. In the plant, feather picking is one of the most problematic areas for transfer of Campylobacter to broiler carcasses. To interrupt this occurrence we tested multiple interventions including plugging the vent, placing bactericidal food grade chemicals into the vent, applying antimicrobials during picking and changing the order of processing events and some of these interventions have been effective in reducing Campylobacter. Additionally, some of these intervention strategies also successfully lessened broiler carcass contamination with Salmonella. Overall, Salmonella prevalence and Campylobacter numbers are significantly lessened through modern processing and intervention techniques. Further research and ongoing optimization of processing parameters will continue to help processors as they improve the microbiological quality of poultry meat products.
Technical Abstract: When market age broilers are transported to processing plants, feces from individual birds in a Campylobacter positive flock can contaminate transport containers (1). Feces, and therefore Campylobacter, is deposited on the floor surface of transport cages. When placed in soiled transport cages previously used to transport Campylobacter positive chickens, a flock that was originally Campylobacter free can become contaminated (2). In 2004, Northcutt and Jones (3) found that only about 28% of U.S. processing plants were actively washing cages between uses. Although washing and sanitizing has been shown to significantly lower the number of Campylobacter on transport cage flooring, it is not always adequate to remove all Campylobacter (4). Campylobacter is sensitive to dry stress. Allowing feces left on transport cage flooring to dry during extended periods of non-use has been shown to be effective to lower the numbers of viable Campylobacter left by positive flocks (5, 6). One problem with this approach is that poultry processors don’t have time, space or resources to maintain several times the minimum required number of transport cages. Application of absorbent corn starch or forced hot air as drying agents for fecal matter left on spray washed or unwashed coop floor surfaces is helpful to lessen contamination with Campylobacter in as little as 15 min. (7, 8). In the slaughter plant, various modifications to processes can be helpful to lessen contamination of broiler carcasses. A scald water additive (lime slurry) was used to increase the pH of scald water at a commercial processing plant from near neutral (approximately 7.0) to a more basic 9.89 in an attempt to lessen Campylobacter and Salmonella contamination before feather removal. Carcasses subjected to the high pH scald were less contaminated with Campylobacter but not significantly less (P>0.05) likely to be contaminated with Salmonella than those treated by standard scald. (9) Moderating increased microbial contamination during defeathering has been the goal of multiple research projects conducted by ARS at Russell Research Center. One such project was conducted in a commercial plant and involved application of chlorine dioxide through existing plumbing in feather picking machines (10). Control carcasses picked with a standard water spray were collected first. Then, site generated chlorine dioxide was sprayed through the feather picker drip line at 50 ppm. Carcasses sprayed with chlorine dioxide during defeathering had significantly lower (P<0.05) numbers of Campylobacter and decreased prevalence of Salmonella than control defeathering (11). Commercial broiler processors employ various spray and brush washers on both the kill and evisceration lines. A study was conducted to examine the efficacy of multiple wash steps in a commercial broiler slaughter plant. Washers tested included: pre-scald brush washer, post-feather pick spray washer, inside/outside spray washer, subsequent brush washer and a final pre-chill spray washer. All washers were operated with chlorinated water (approximately 40 ppm). Overall, numbers of Campylobacter were lowered and Salmonella prevalence was reduced however, no single wash step caused a significant decrease by itself (12). Finally, chemical processing aids are approved for use in U.S. commercial broiler processing to lessen microbial contamination. In 2006-2007 a year-long study was conducted in 20 randomly selected large commercial broiler plants across the USA. This study represented eight integrated poultry companies operating in thirteen different states. Each plant used different combinations of processing aids. Carcasses were collected at re-hang and again from the same flock post-chill to determine Campylobacter numbers and Salmonella prevalence. Each plant was visited four times for a total of 8